INHIBITION OF [H-3] MEBENDAZOLE BINDING TO TUBULIN BY STRUCTURALLY DIVERSE MICROTUBULE INHIBITORS WHICH INTERACT AT THE COLCHICINE BINDING-SITE

A rapid and convenient radioligand assay was used to characterise the interaction of several structurally diverse microtubule inhibitors wit h the colchicine binding domain of tubulin. Values determined for the inhibition of [H-3]mebendazole binding to tubulin by colchicine, combr etastatin A4, NSC 181928, NSC 321567, podophyllotoxin and tubulozole-C provided an independent measure of the relative potency of these comp ounds. This methodology has several advantages over the inhibition of [H-3]colchicine binding as a technique for investigating the molecular mechanisms involved in determining tubulin-ligand interactions.